Hot Water Recirculation, Watts 500800

Installed one of these, wife absolutely loves it. Suggestion for those wanting to install, buy the sensor kit first (~$50) and install on farthest sink, before buying pump kit. The valve itself seems to work pretty well without a pump necessary. I believe simple thermodynamics is enough to cause the water to circulate well enough in this system. I run the pump a few hours in the morning, but the hot water is fairly quick 24/7 ,even without pump operating. Worst case, is you end up buying the pump and have an extra sensor. Think many homes may benefit with two sensors anyway.

My wife has been complaining about how long it takes for the hot water to arrive in her upstairs bath. I've been looking at the Grundfos Instant Hot Water Recirculation Kit and wonder if you compared the two.

My only problem is she absolutely hates the new rental powervent gas water heater I recently had installed and wants it gone. She wants me to install a tankless but I don't think they are quite what they're made out to be and AFAIK they are not compatible with any Instant Hot Water Recirculation Kit. There's a minimum (0.6 or there about) GPM required for a tankless to fire.

I believe there is a recirculating system that does not use a pump, but I think the type with a dedicated return line is best when possible to install. My system does not have a timer, and I don't even know what the sensors you refer to all. My Laing pump has been running 24/7 for several years with no problem. I do not have experience with a Watts system, but I think it is probably very similar. As far as tankless water heaters are concerned, there are those who really think they are great, but most of us are not of that opinion. A couple of things you should realize about them. They require a larger gas supply that is found in a standard residence. It's very expensive to get the larger supply installed. Tankless also require periodic cleaning, and servicing. It is hard to find qualified people to do this. If your incoming water is quite cold in the winter, you may have a problem getting enough really hot water. They are very expensive to buy and install. While the advocates of tankless will argue this, it has been reported that the money savings over time will not beat a good gas heater. You don't say what it is about your power vent that you wife doesn't like, and I can't think of any d

The Grundfos/Watts recirc system uses a principle of a slight pressure head on the hot line and a temperature sensing valve with crossover to the cold side at the remote end. It is designed as a retrofit where a dedicated return line is not practical to intstall.

IKWYM about the gas supply on tankless. The entire supply from the curb needs to be verified, not just the last few feet from the meter to the heater. The two reasons the wife wants tankless is she bought into the hype and she wants to use the space the tank occupies for a pantry. We had a passive vent State tank which was very quiet and took its air from outside so no reverse cold draft when the burner is off. The powervent is loud and because the burners are open to the air in the room, they have a subsonic rumble like a train idling in the distance. One can feel the rumble in the chest depending on where one stands. When the burner is off, the vent reverses, letting in cold air. I miss my State tank but they stopped making the model I had and the current model is too tall to go out the existing hole on the wall. Someone should come out with a horizontal tank gas water heater that would fit in my crawlspace like my low-boy furnace does. That way the wife could have her pantry space, the noise would be further away, and it would be better than a tankless.